The major function of absorbent articles such as disposable diapers and adult incontinent briefs is to absorb and contain body exudates. Such articles are thus intended to prevent body exudates from soiling, wetting, or otherwise contaminating clothing or other articles, such as bedding, that come in contact with the wearer. Absorbent articles thus function both to contain the discharged materials and to isolate these materials form the body of the wearer and from the wearer's garments and bed clothing. However, absorbent articles have a tendency to sag or gap away form and to slide/slip down on the body of the wearer during wear. This sagging/gapping and sliding/slipping is caused by the relative motions of the wearer as the wearer breathes, moves and changes positions, by the downward forces generated when the absorbent article is loaded with body exudates, and by the deformation of the materials of the absorbent article itself when subjected to such wearer's motions. This sagging/gapping and sliding/slipping of the absorbent article can lead to premature leakage and poor fit of the absorbent article about the wearer in the waist regions and the regions of the absorbent article.
Disposable absorbent articles have been marketed which include one or more elastic or stretch members to provide improved fit about the waist and legs of the wearer. An example of a disposable diaper with an elastomeric waist feature which has achieved wide acceptance and commercial success is disclosed in U.S. Pat. No. 4,515,595 issued to Kievit and Osterhage on May 7, 1985. Elastic waist features will typically comprise an elasticized waistband consisting of an elastomeric member contractibly affixed between the topsheet and the backsheet. The elasticized waistband is, thus, designed to expand and contract with the wearer's motions and to maintain, the fit of the absorbent article about the waist of the wearer during use. Disposable absorbent articles having elastic leg features are also known to the art. For example, U.S. Pat. No. 3,860,003, entitled “Contractable Side Portions For Disposable Diaper” issued to Buell on Jan. 14, 1975, describes an absorbent article having an elasticized leg cuff which has achieved wide acceptance and commercial success.
Methods for stretching an elastic member are described in U.S. Pat. No. 4,107,364, issued to Sisson on Aug. 15, 1978, U.S. Pat. No. 4,209,563 issued to Sisson on Jun. 24, 1980, U.S. Pat. No. 4,525,407 issued to Ness on Jun. 25, 1985, U.S. Pat. No. 4,834,741 issued to Sabee on May 30, 1989, European Patent Publication 409,315 published Jan. 23, 1991.
Still other methods are described in U.S. Pat. Nos. 5,167,897, 5,156,793, and U.S. patent application Ser. No. 07/662543, each filed Feb. 28, 1991 and assigned to The Procter & Gamble company. These patents describe making an elasticized laminate by mechanically stretching making a zero-strain stretch laminate web to impart the elasticity hereto in the direction of stretching, at least up to the point of initial stretching.
Conventionally, the elastic feature of an absorbent article consists of a laminate web of at least one elongatable, non-elastic nonwoven layer and at least one elastic member with both layers in their relaxed state. The laminate web is elasticized by mechanically stretching at least portions of the laminate web along its width to impart elasticity thereto in the direction of stretching, at least up to the point of initial stretching. The elastomeric web may fist undergo a “cut and slip” operation prior to activation by mechanical stretching, so that it has the required dimensions as the elastic feature of the absorbent circle. Such operations are described in U.S. Pat. Nos. 5,167,897 and 5,156,793 and additionally in U.S. Pat. No. 5,143,679.
In numerous instances the elastic member is a solid, non-breathable member which can cause undue build-up of moisture against the skin of the wearer if the article worn for an extended period of time. In order to solve this problem, apertured elastic members have been used to provide both elasticity and breathability. An example of such a design is shown in U.S. Pat. No. 4,573,991. The elastic member of U.S. Pat. No. 4,573,991 comprises longitudinal and transverse interconnected elastic strands, commonly referred to as elastomeric scrim. One of the drawbacks associated with elastomeric scrim is that the elongation forces are not uniform in all directions. Furthermore, the scrim has a very uneven surface as the portion of the scrim where the strands overlap are bumpy and can lead to skin irritations.
It is an object to solve the problems presented by the use of scrims by providing an apertured elastomeric member which has substantially uniform elongation forces and has a very even or uniform thickness dimension throughout.